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The VLFeat MATLAB toolbox provides implementations of common
computer vision algorithms (SIFT, MSER, AIB, KMEANS, ...) and
other useful MATLAB functions, some of which are listed next:
</p><ul><li><p>
<a href="VL_SIFT.html">VL_SIFT</a>() computes the Scale-Invariant Feature Transform.  SIFT
bundels the most widely used feature detector and
descriptor. This version is compatbile with Lowe's original
implementation.
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<a href="VL_MSER.html">VL_MSER</a>() computes the Maximally-Stable Extremal Regions of an
image. It detects features corresponding to stable image level
sets.
</p></li><li><p>
<a href="VL_IKMEANS.html">VL_IKMEANS</a>() and <a href="VL_HIKMEANS.html">VL_HIKMEANS</a>() are basic implementations of K-means
and hierarchical IKM optimized to work on integer data
types. This is useful to quantize large collection of features,
for instance to create visual dictionaries.
</p></li><li><p>
<a href="VL_AIB.html">VL_AIB</a>() uses the AIB algorithm to discriminatively compress a
discrete random variable. An application is the compresssion
of a visual dictionary for categorization.
</p></li><li><p>
<a href="VL_IMARRAY.html">VL_IMARRAY</a>() and <a href="VL_IMARRAYSC.html">VL_IMARRAYSC</a>() tile image stacks, <a href="VL_IMSC.html">VL_IMSC</a>()
scales the range of an image, <a href="VL_IMSMOOTH.html">VL_IMSMOOTH</a>() convolves an image
by a number of different kernels, <a href="VL_IMWBACKWARD.html">VL_IMWBACKWARD</a>() warps an
image by backward mapping, <a href="VL_WAFFINE.html">VL_WAFFINE</a>(), <a href="VL_WTPS.html">VL_WTPS</a>(), <a href="VL_WITPS.html">VL_WITPS</a>()
compute various kind of image warps, <a href="VL_IMWHITEN.html">VL_IMWHITEN</a>() whitens an
image, <a href="VL_XYZ2LAB.html">VL_XYZ2LAB</a>(), <a href="VL_XYZ2LUV.html">VL_XYZ2LUV</a>(), <a href="VL_XYZ2RGB.html">VL_XYZ2RGB</a>(), <a href="VL_RGB2XYZ.html">VL_RGB2XYZ</a>()
perform basic color space conversions.
</p></li><li><p>
<a href="VL_CF.html">VL_CF</a>() to copies a figure, <a href="VL_TIGHTSUBPLOT.html">VL_TIGHTSUBPLOT</a>() provides a
&quot;borderless&quot; version of SUBPLOT(), <a href="VL_CLICK.html">VL_CLICK</a>() and
<a href="VL_CLICKPOINT.html">VL_CLICKPOINT</a>() interactively select image points,
<a href="VL_PRINTSIZE.html">VL_PRINTSIZE</a>() scales a figure printing size to a fraction of
the default paper size, <a href="VL_PLOTFRAME.html">VL_PLOTFRAME</a>() to plot feature frames
(points, disks, oriented disks, ellipses, oriented ellpises).
</p></li><li><p>
<a href="VL_BINSUM.html">VL_BINSUM</a>() computeds binned summations (and compute
histograms), <a href="VL_TWISTER.html">VL_TWISTER</a>() controls and runs VLFeat internal
random number generator (useful to reproduce results from
randomized algorithms), <a href="VL_WHISTC.html">VL_WHISTC</a>() computes weighed histograms,
<a href="VL_GRAD.html">VL_GRAD</a>() computes the gradient of a 2-D function.
</p></li></ul><p>
See also: http://www.vlfeat.org.
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